1. Field of the Invention
The present invention relates to an image sensing apparatus and a method for controlling the same.
2. Description of the Related Art
Some conventional image sensing apparatuses such as a digital still camera determine various conditions such as the brightness, color, distance, and motion of a sequentially sensed subject, and calculate the evaluation value of scene determination representing the condition of the subject. An image sensing apparatus of this type senses an image in accordance with a scene specified by the calculated evaluation value of scene determination and a result of a face detection. For example, Japanese Patent Laid-Open No. 2008-287091 discloses a technique for sensing an image corresponding to a scene. According to this technique, a backlight scene is detected based on the evaluation value of scene determination representing the brightness difference between an area estimated to contain a main subject and the remaining area. And the exposure control is done to cancel the backlight.
However, a narrow dynamic range of an image sensor arises as a problem when determining various conditions such as the brightness, color, distance, and motion of a subject by the image sensor such as a CCD image sensor or CMOS image sensor. The image sensor used to sense still images and moving images doesn't have enough dynamic range and is not suitable for photometry of a scene which greatly changes the brightness difference. If the exposure is improper, highlight detail loss at a bright area and shadow detail loss at a dark area stand out. Even if it is tried to detect various conditions such as the brightness, color, distance, and motion of a sequentially sensed subject, appropriate detection may fail. If a scene is determined in this situation, image sensing based on the determination result sometimes leads to an unnatural image.